Various processes are known to code a bandwidth-limited signal in order to compress the bandwidth of the signal, and then to decode such a coded signal. These methods are usually based on various technologies, such as for example linear predicting code (LPC), partial band coding, and the like. These known methods can be used only with very specific types of signals, for example signals representing speech, in which reduction factors of from 2 to 4 are possible without perceptible loss of signal quality.